The present invention refers to a light radiator for effectively diffusing and radiating light rays outside of the optical conductor cable through which they were transmitted.
The present application has previously proposed various ways to focus solar rays or artificial light rays through the use of lenses or the like, in order to guide them into an optical conductor cable, and thereby transmitting them onto an optional desired place. The solar rays or artificial light rays transmitted and emitted in such a way are employed for photo-synthesis and for use in illumination or for other like purposes such as for promoting the growth of plants.
However, in the case of utilizing light energy for cultivating plants, the light rays transmitted through the optical conductor cable have directional characteristics. Supposing that the end portion of the optical conductor cable is cut off and the light rays are emitted therefrom, then the radiation angle for the focused light rays is, in general, equal to about 46.degree.. That is quite a narrow field. In the case of utilizing the light energy as described above, it is impossible to perform a desirable amount of illumination by simply cutting off the end portion of the optical conductor cable and by letting the light rays emit from it.
Therefore, the present applicant has already proposed various kinds of light radiators capable of effectively diffusing light rays which have been transmitted through an optical conductor cable and by radiating the same for the purpose of illumination over a desired area.